German police say they have thwarted a plot by two students to carry out a massacre at their school.
One suspect, aged 17, committed suicide after being questioned about the plot and his alleged accomplice, 18, is under arrest, police said.
A school in the western city of Cologne is believed to have been the target.
Police were alerted last week after the suspects were spotted by classmates studying pictures of the Columbine school massacre in the US in 1999.
'Hurt and kill'
The two teenagers had planned to attack Cologne's Georg-Buechner high school on Tuesday, police said.
"They wanted to hurt and kill people, and then take their own lives," Norbert Wagner, the chief investigator in the Cologne case, told reporters.
The school's head teacher alerted police on Friday after classmates saw the two boys studying a website with images of the Columbine massacre.
The 17-year-old was questioned on Friday. He was then allowed to go home on his own but during the journey he threw himself under a tram and died of his injuries, police said.
The second suspect was also quizzed and confessed to the plot, Mr Wagner said.
Air guns and crossbows were later found during searches at the suspects' homes. A possible hit list of students and teachers was also discovered.
The names of the two suspects have not been released.
Last year, a former pupil injured several students in Germany's western town of Emsdetten before turning the gun on himself.
In 2002, a former pupil killed 18 people in his school in the eastern city of Erfurt. The gunman then killed himself.
In the Columbine massacre in the US, two teenagers shot dead 12 classmates and a teacher before killing themselves.